The identification of objects in an image and determination of their position and orientation relative to some coordinate system is one of the fundamental tasks addressed to in the field of computer vision. The information comprising the position and orientation of an object is typically referred to as the “pose” of the object. The task of determining the pose of an object in an image is typically referred to as “pose estimation” or “pose detection”.
An image captured by a camera is typically a projection of a three dimensional scene onto a two dimensional plane. Under the transformation, an object may appear in image coordinates as rotated and translated relative to real world coordinates. The transformation may also introduce a perspective distortion causing parallel lines to appear as intersecting. For example, a rectangular object may appear in the image as trapezoidal. Such distortions and displacements may be eliminated by a process referred to as “image rectification” or “image de-warping”, in which the image is projected onto a different plane. The information of a pose of an object may be useful for performing image rectification, for example if the geometry of the physical object is known, as in the case of a rectangle shape.